| Exam Board | Edexcel |
|---|---|
| Module | S1 (Statistics 1) |
| Marks | 4 |
| Paper | Download PDF ↗ |
| Mark scheme | Download PDF ↗ |
| Topic | Discrete Probability Distributions |
| Type | Direct probability from given distribution |
| Difficulty | Easy -1.8 This is a pure recall question requiring only definitions and simple examples of random variables. No calculations, problem-solving, or application of techniques needed—just stating what a random variable is and giving basic examples like 'number of heads in coin tosses' or 'height of students'. |
| Spec | 5.02a Discrete probability distributions: general5.03a Continuous random variables: pdf and cdf |
| Answer | Marks | Guidance |
|---|---|---|
| (a) A numerical quantity determined by the outcome of an experiment, taking different values with certain probabilities | B2 | |
| (b) (i) e.g. shoe size | B1 B1 | (ii) e.g. time, in s, to run a race |
(a) A numerical quantity determined by the outcome of an experiment, taking different values with certain probabilities | B2 |
(b) (i) e.g. shoe size | B1 B1 | (ii) e.g. time, in s, to run a race | | Total: 4 marks
---\begin{enumerate}[label=(\alph*)]
\item Explain briefly what is meant by a random variable. [2 marks]
\item Write down a quantity which could be modelled as
\begin{enumerate}[label=(\roman*)]
\item a discrete random variable,
\item a continuous random variable.
\end{enumerate}
[2 marks]
\end{enumerate}
\hfill \mbox{\textit{Edexcel S1 Q1 [4]}}